Japanese Patent Publication No. 33523/1977 discloses a method of recording halftone images comprising the steps of splitting a light beam from a light source into a plurality of light beams by a combination of half mirrors and mirrors, and independently controlling the individual light beams in response to image signals from an original by an electro-optic light modulating element disposed correspondingly to the individual light beams. Japanese Patent Application Disclosure Nos. 118302/1977 and 12370/1977 disclose methods of recording halftone images comprising the steps of splitting a light beam from a light source into a plurality of light beams by a light beam splitter having parallel flat surfaces coated with a special film, and independently controlling, as in said Japanese Patent Application No. 33523/1977, the individual light beams in response to image signals from an original by an electro-optic light modulating element.
However, the electro-optic light modulating elements used in such conventional methods, when actually used, require a temperature control device since they are influenced by ambient temperature variations to a great extent, as described in said Japanese Patent Publication No. 33523/1977, thus having the drawback of increasing the size of the whole device. Further, to effect perfect modulation, i.e., ON-OFF control of the individual light beams, it is necessary to apply a bias voltage to the electro-optic modulating element, thus presenting drawbacks in regard to the circuit arrangement.
Furthermore, the light beam splitters used in these conventional methods each have their drawbacks. More particularly, with the light beam splitter disclosed in Japanese Patent Publication No. 33523/1975, which is constituted of a combination of half mirrors and mirrors, light beam splitting is effected by the light beam passing successively through the half mirrors, thus having a drawback that the light beams become nonuniform in intensity. On the other hand, the light beam splitter used in Japanese Patent Application Disclosure No. 118302/1977 must be increased in size as the number of light beams into which the light beam is split is increased, and as the splitter is increased in size, the parallelism between the light beam receiving and emitting surfaces becomes more difficult to attain, causing the further drawback of increasing the cost of production.
As will be described in greater detail hereinafter, the present invention provides an image scanning and recording device which eliminates these disadvantages.